I have written about climate change and energy policy for more than 25 years. I have come to the conclusion that current energy and climate policy is probably more dangerous, both economically and ecologically, than climate change itself. This is not the same as arguing that climate has not changed or that mankind is not partly responsible. That the climate has changed because of man-made carbon dioxide I fully accept. What I do not accept is that the change is or will be damaging, or that current policy would prevent it. For the benefit of supporters of climate change policy who feel frustrated by the reluctance of people like me to accept their assurances, here is what they would need to do to change my mind.

A global view of the Earth at night, compiled from more than 400 satellite images. Researchers have suggested that heat generated by large cities can alter the climate thousands of miles away. The 'waste heat' from buildings, factories and road vehicles disrupts atmospheric systems that affect the weather over great distances, it is claimed.

Now I don't have the scientific brain of the cockroach obviously but personal experience tells me that the UHI is considerably more than Jones' rather pathetic 0.5C of 20 years ago.Most of the rest of Ridley's article makes sense as well.As he says, we are taking chemotherapy for a cold.

What about a test for us non-lukewarmers. A convincing proof that re-radiated radiation from a cold atmosphere to a warmer surface warms that surface as claimed by the IPCC statement that

Much of this thermal radiation emitted by the land and ocean is absorbed by the atmosphere, including clouds, and re-radiated back to Earth. This is called the greenhouse effect. The glass walls in a greenhouse reduce airflow and increase the temperature of the air inside. Analogously, but through a different physical process, the Earth’s greenhouse effect warms the surface of the planet.

For my money , Ridley is the best science communicator of his time (Right Reverend present company excepted ;-)

His combines clarity and common sense in a way that manages to cut right through the smoke & mirrors techno-babble of the climate snake oil merchants.

His ten points perfectly summarise the key deficiencies in the the official narrative - and it's easy to see how they can drive the professional doom cultists (who had better remain nameless) to impotent, frothing rage.

"That the climate has changed because of man-made carbon dioxide I fully accept."

Thank you Buddy the Elf. Santa won't be needing you next year. He did not appreciate you setting fire to his factory while promoting yourself as his best friend. Never, mind, there will always be a job for you at Northern Rock.

"That the climate has changed because of man-made carbon dioxide I fully accept."

Matt - if you are reading here, please can you give us the top three peices of numerical evidence which led you to this position? I couldn't find any evidence to support this statement in your paper. Thanks.

What about a test for us non-lukewarmers. A convincing proof that re-radiated radiation from a cold atmosphere to a warmer surface warms that surface as claimed by the IPCC statement that

Much of this thermal radiation emitted by the land and ocean is absorbed by the atmosphere, including clouds, and re-radiated back to Earth. This is called the greenhouse effect. The glass walls in a greenhouse reduce airflow and increase the temperature of the air inside. Analogously, but through a different physical process, the Earth’s greenhouse effect warms the surface of the planet.

Jan 28, 2013 at 5:52 PM Phillip Bratby

Phillip, If Matt Ridley had asked for such a test, I'd have assumed he was masquerading as My Dog's Got No Nose. Or vice versa.

The IPCC explanation of the greeenhouse effect is gobbledegook, but the fact that they gave a gobbledegook explanation does not mean that the GHE itself is itself a fiction.

The GHE can be explained without any need to talk about radiation from cold things heating hot things. All the initial heating is done by incoming radiation from the Sun. Once things have warmed up and are in equilibrium, there is no more heating being done. If you use standard black body theory to calculate the equilibrium conditions, it explains the GHE*. But I imagine you have heard all that before.

* With approximations (such as assuming surface temperature is uniform) that make the analysis little better than a plausibility argument. But with nothing assumed that contradicts the laws of physics.

Ridley’s article is excellent, except for the reference to Pascal’s wager in the second to last paragraph. Pascal’s wager is still a good bet: “Believe, and be saved - at no cost.” The Precautionary Principle is rather different: “Believe, and be saved (perhaps) at the price of a reduced standard of living for you and your descendants for ever more”.

Martin A; But it's the assumption of a uniform surface temperature that makes it nonsense. If the GHE can be explained without any need to talk about radiation from cold things heating hot things, why doesn't the IPCC, or the Met Office or all those other august bodies give a cogent explanation? Answer: becasue there isn't one.

Foxgoose: The GWPF seems to have the two best science communicators of the present time, Matt Ridley and David Whitehouse. Invidious to put one first I know but Whitehouse first and then Ridley. Nigel Lawson knows what he is doing!

The point is, even fully accepting the mainstream CO2 warming theory, Matt Ridley's challenges hold. As they do for many sceptic scientists on the GWPF advisory council and a whole lot more, as well as the political/economic sceptics like Lawson Klaus Lilley and increasingly many others in the political arena including Labour's Graham Stringer.

It seems irrelevant whether you "fully accept" CO2's role or not. Matt Ridley seems to be playing a tactical game by showing that it is possible to take the IPCC viewpoint (other than the value of climate sensitivity) and still challenge most of the main issues

To my mind the point is that Matt's challenges hold without fully accepting the mainstream "man-made-climate-change-through-CO2-emissions" story. As you do, he could say "....even if the mainstream theory of MMCCTCO2E is assumed true, it needs to address these challenges....".

But he doesn't. Instead he says he fully accepts it:

"That the climate has changed because of man-made carbon dioxide I fully accept."

and, in my opinion, if he wants to be taken seriously as a rational commentator he needs to be able to explain what has convinced him that this is the case.

It is a pity that the CAGW crowd are too cowardly to debate. A public debate on these points and others would be most interesting.

Jan 28, 2013 at 6:00 PM | ConfusedPhoton

Unfortunately most of the public debates, on talk shows and the like, have involved scientists wishing to discuss the science and sceptics wishing to score political or idealogical debating points. They tend to demonstrate the unwillingness of scientists to discuss politics and the unwillingness of sceptics to discuss science.

There have been discussions on the subject where both sides have been able to interact without the politics, organised by the Royal Society

There is also a site which organised a scientific discussion between representatives of the two sides online with some success. Dr Curry took part.

Martin A; But it's the assumption of a uniform surface temperature that makes it nonsense. If the GHE can be explained without any need to talk about radiation from cold things heating hot things, why doesn't the IPCC, or the Met Office or all those other august bodies give a cogent explanation? Answer: becasue there isn't one.Jan 28, 2013 at 8:22 PM Phillip Bratby

Phillip,

Following on from my 8:31 response, having thought about it a bit more....

The IPCC gobbledegook explanation of the GHE is not due to incompetence. It is due to dishonesty.

I am sure that after they drafted a proper explanation, someone said "Nobody is going to make head nor tail of that, with all this talk of 'equilibrium', 'T-to-the-fourth-power' and so on; re-write it so that even Chris Huhne could understand it".

So they did what Richard Feynman cautioned against - giving a false/oversimplified explanation that seems to make sense to someone who does not understand physics or who does not think carefully about what you have said. But which is actually a form of lying, because you are:

- Knowingly not telling the truth.

- Convincing someone to believe what you wish them to believe by means of a falsehood.

I would add another point.Any large scale project requires effective management to achieve the planned objectives. Even if there was a demonstrable enormous potential problem and and a set of appropriate policies implemented that is theoretically capable of combating that problem, without detailed project management huge amounts of money can be expended without getting any desired results. Matt Ridley’s allusion to the medical sphere – of taking chemotherapy for a cold – can be extended further. There is a diagnosis of the early stages of an entirely new disease. We only have a vague idea of how severe this disease might develop, with little attempt to revise downwards the initial diagnosis following a distinct lack of distinctive strong signs of progress of the disease. The symptoms are faint, and evidence that they might belong to the normal variations of life is ignored. The treatments are untested, possibly ineffective, and have emerging debilitating and painful side effects. Yet the professionals ignore these signals. Furthermore the prescribers have scant regard for dosage, and do not monitor the progress of the patient.

FWIW - this is Matt's comment at WUWT where others have been questioning his position:

"Thanks for the comments. I don’t (yet!) question the greenhouse properties of CO2, because I convinced myself a few years ago that the physics is sound, but of course I’ll retain an open mind."

So, no numbers, no evidence - just an appeal to "sound physics". If you are reading Matt, and you'd care to expand on how you step from what appears to be a reference to radiative properties of a trace gas in the atmosphere, to the certainty that the climate has changed because of the man made portion of it, as I say above, I'd be very pleased to see your top three pieces of evidence. Thanks.

Martin A 7.56pmIf you don't like the phraseology, take it up with Ridley. I was quoting him.And on the subject of greenhouses and black bodies, yes we have "heard it before" as you have probably heard me say the earth is not a black body and the earth's atmosphere — since it is open at the top — does not in any way behave like a greenhouse.Perhaps the sooner we get away from these hyper-simplistic aides memoires and use our intellect instead of our imagination the sooner we might be able to make some attempt at addressing the world as it is, something which I note you make some movement towards in your 9.43 response to Phillip Bratby.There is hardly a simpler soul around than me (in terms of really trying to get to grips with the physics) but even I know that describing things as something they are not in order to make it simple for the hard-of-thinking only ends up with the hard-of-thinking being led by the nose.Which is precisely what has happened for the last 20 years.And I contend that as long as we even pay lip service to the idea of treating the earth as a black body or the atmosphere as a greenhouse "for the sake of simplicity" then we will continue down that well-worn path.Just sayin'.

But I will remain open-minded to persuasive evidence that the greenhouse effect is a myth, just as I remain open-minded to persuasive evidence that global warming will be more dangerous than global warming policies. At the moment I find both of those extreme positions equally unpersuasive.

I agree that Matt's arguments stand up to the assertion that he believes in the CO2 greenhouse effect. As others point out though it would be good of Matt to point to his references that make him believe that in the first place. That in itself would be a good indicator of how he goes from that initial 'lukewarmer' assertion to his 10 questions which are mostly much more sceptical. One of them even shows natural variability showing warmer periods in the past on 2 occasions.

While the CO2 theory does have a vague basis in physics to put it into the initially plausible effect camp, one of my biggest problems is the sheer amount of water vapour around in the atmosphere that surely dominates any supposed 'greenhouse' effect. Surely the water cycle (and the infinite reserve of liquid water in oceans and clouds) and changes within it over many different time cycles must be dominant over any possible CO2 effect if there is any.

I just love the way that sceptics gang up against other sceptics on knit-picking arguments. Why do you guys try to subvert yourselves all the time? Why do you have this need to represent yourself as frenzied crazies? Why can you not just accept the tactical argument of agreeing with the other side's key postulate and then destroying it?

Thanks for the reference Matt. However unlike you I do not find it an easily understood essay - it strikes me as a scatter gun response to a scatter gun argument. Please can you point me to the relevant parts which make the convincing case that mankind's emissions of CO2 have undoubtedly changed the climate.

Please can you also give me two more of your top three references in support of your statement:

"That the climate has changed because of man-made carbon dioxide I fully accept."

"His ten points perfectly summarise the key deficiencies in the the official narrative - and it's easy to see how they can drive the professional doom cultists (who had better remain nameless) to impotent, frothing rage.

I am with you to a degree. The ten points are excellent and I would like to post a link in a forum where "warmists" hold sway. However, the "professional doom cultists" there will merely skim through the footnotes, find no references to any peer-reviewed journals, only blogs, and will dismiss it all on that basis.

Matt, I see you have pointed out more than once that you are open minded on the issue. I've only skimmed the reference but it is a more an argument of why the 'Sky Dragons' are wrong rather than why the greenhouse theory is right. I'm not particularly interested in why other theories are wrong.

I have issues with the basic description of the greenhouse effect from the start of the article. It is just way too simplistic in describing what is happening on the Earth in it's daily/yearly and other cycles. As I said I agree with your 10 tests no matter what effect CO2 may be having in the atmosphere.

"Without any IR-absorbing GHGs in the atmosphere, all radiative energy losses balancing solar input would occur at Earth’s surface. According to the laws of radiation, the average temperature at the surface would then be about -18⁰C, nearly 33⁰C colder than the observed mean value. While IR is radiated to space from the surface and atmosphere, the average loss occurs where the temperature is actually -18⁰C at an altitude of around 5km. The more GHGs in the atmosphere the higher this average radiative layer; and since the temperature below it increases by about 6.5⁰C/km (the lapse rate), the higher this layer the higher the temperature at Earth’s surface. This critique will examine only the basics of this very complex subject."

[1] Sorry - I did not mean to give the impression that you had said something that needed correcting but I can see that's the impression I gave. I was just trying to make the point that Ridley's "cold" has not, in my opinion yet been verified. So taking something to cure it in advance of knowing it is there is premature.

[2] The oversimplified GHE explanations don't convince me of anything because of their gross approximations and the important, perhaps dominant, effects they neglect. The point I have tried to make a number of times is that pointing out that the model is oversimplified to the point of irrelevance is a different thing from claiming that its analysis violates the laws of physics.

Matt - apologies if this duplicates a point from me which subsequently appears, but the Jo Nova hosted article you cite is a very poorly structured response to multiple tangential arguments.

I am sure you appreciate there is a difference between admitting that something may be possible and fully accepting it, so I repeat:

What is your evidence that climate has changed due to man made CO2 emissions? What are the numbers that convinced you that this has happened? (If indeed you are convinced - your comment at 10:37pm appears to hedge somewhat?) If that evidence is in the Jo Nova guest article please provide a page reference.

Or are you, as diogenes suggests, playing some sort of "tactical game" and therefore you cannot evidence your stated position?

"I have read many papers that convince me that CO2 and water vapour raise atmospheric temperatures by trapping OLR. But I will remain open-minded to persuasive evidence that the greenhouse effect is a myth"

This is what separates celebrities from mere mortals. Matt Ridley can do vastly complex calculations in his head that normally require highly trained scientists and sometimes millions of dollars of hardware and software called climate models.

Next, without the use of a cigarette packet or a pen, Matt will tell us that he believes the big bang happened 50 million years ago because he understands Newton's Laws of Motion.

"Those struggling with the greenhouse effect may find these posts from Wattsupwiththat useful."

Those struggling with the concept of complexity can stick their head in a bee hive and do a calculation of the position of each bee and the temperature of the hive twelve hours later. You may need pencil and paper for this.

That just isn't a very useful analogy apart from at an extremely basic level - It doesn't even have an atmosphere in the model. I'm a big fan of very simple models but the key component that always seems to be missed out in these 'radiation' examples is the dominant role of convection in the Earth's Troposphere. If you don't include convection in your model (you can't just assume a constant lapse rate to cover the effect) then your model is a bad example of the Earths atmosphere. The key role of convection is to try and cool the Earth's surface (by moving the hotter air upwards) when anything tries to warm it, so it is obviously clear the effect is very important.

Geoff Chambers, Pascal's Wager is a piece of nonsense. The problem is, believe what? You have millions of choices that people have already thought of, plus as many as your imagination can conceive. All of them may be wrong. Amusingly made obvious by Rowan Atkinson.

Why is it that people are assuming that warming has stagnated for 16 years because of "natural variations"? Those people have no idea what the "natural variations" are and until they know, they should reserve judgement.It seems far more plausible to assume that CO2 is not warming the planet.

To call the footnotes disappointing is an understatement. Surely he could have found some better sourcing for his observations than those links?

The basic argument is sound and pointed. But its completely undermined by the sources. The information supplied could have been properly sourced.with a few minutes work either from him or a competent research assistant. Very disappointing.

On the basic greenhouse effect, I like Konrad's arguments on WUWT.iehttp://wattsupwiththat.com/2013/01/28/matt-ridley-a-lukewarmers-ten-tests/#comment-1211354http://wattsupwiththat.com/2013/01/28/matt-ridley-a-lukewarmers-ten-tests/#comment-1211463http://wattsupwiththat.com/2013/01/28/matt-ridley-a-lukewarmers-ten-tests/#comment-1211480

Has someone shown what the atmosphere would definitively be like with no 'greenhouse' properties. ie say a pure Nitrogen atmosphere. It would still heat by conduction from the surface but have no way of radiating the heat away, so surely has to be warmer than the -33 degrees or whatever attributed to the greenhouse effect, would it be isothermal in equilibrium?. Even a very small amount of radiative gas added to that pure N2 atmosphere (making the assumption it can't radiate away energy at all) is going to change it's properties in a massive way as explained well by Konrad. I guess I'm in the small amounts of greenhouse gases effect the Earth in a really big way but adding more now won't make any real difference camp...... assuming there is a camp for that theory.

The slayers are becoming a nuisance here, their bigotry no longer confined to the appropriate threads, and now attacking one of the scant few respected public figures on the rational side. The CAGWers must be rubbing their hands with glee at the self-destruction on view.

Martin, Matt, et al. There is no way you can convince slayers of the science of greenhouse warming, because their position was not arrived at via science. No matter how many times you show them evidence, they just repeat the question as if you didn't answer it. If they admit they might have been wrong about one aspect of their ideology, that means they may have been wrong about all of it, and that cannot be allowed to happen. They are becoming as shrill as the CAGW zealots.

They now seem determined to bring down the good ship BH with endless bickering on any and every thread.

Jan 28, 2013 at 11:39 PM | Registered CommenterMartin A Point taken, Martin, but I stand by my contention that using examples which may be theoretically sound or have value in explaining things to the simple-minded (like politicians?) end up being counter-productive if they don't actually address the real world.And as Rob Burton points out further down, where is convection in all this? The whole edifice appears to be based on the effects of radiation and the absorptive characteristics of CO2 even though the relationship between increased CO2 levels and temperature becomes more questionable by the day.

Yes every thread seems to turn to GHE and we all have our views no doubt - overall I am near to the camp promulgated by Rob Burton.

BUT that is irrelevant in this discussion (and I see as I write this that the Bish has forbidden such anyway). We the sceptics come in many guises and discuss our views on here and elsewhere, which may have a commonality but are quite diverse - politically as well as scientifically.

We are often portrayed as extreme people way down one end of the curve, when in reality most of us are close to the norm. Scepticism is about having an open mind, not a closed one.

GWPF have always taken the stance that, while many of their scientific advisers might take a firm view, they would not slavishly oppose policy on purely scientific grounds but on economic and practical ones as well. After all if we wait until we have won the scientific argument, to reverse some of the stupidity put in place, we will already be ruined.

Nothing practical and real world will be achieved sitting around arguing over the GHE, as interesting as it is scientifically.

An excellent set of points by Matt Ridley completely derailed on this site by the fanatics getting bogged down by just a single sentence that mentions CO2.

If Matt had started by saying he didn't accept that CO2 can have some effect, then pretty much every one of the members of the audience for this document would have stopped reading at that point, and in my view, rightly so. Not because the CO2 effect is proven, but because it has nothing to do with the argument!

What I find more worrying than the CO2 point is that this was published by GWPF. I looked in Matt's own site for an alternative source but couldn't find one. I would like to push this document out to freinds and family and acquaintances but being on a GWPF page means they wouldn't read it.